3 week old Toulouse Goose has problems walking now!

:| I can't figure it out! I have a pair of Toulouse geese. One is very active. I have always noticed the other has a problem walking. It looked like the goose was clumsy and couldn't balance. Well, today it is hard for the goose to stand up. But she does to get to the feed and water. I noticed yesterday when I started taking them outside to run and eat grass, she couldn't keep up. We had to wait for her all the time. I assumed that they need exercise. It rained a lot last night and today and I couldn't take them out. They have a huge cardboard box with newspaper print underneath burlap. They have plenty of heat. About 88 degrees right now. I just can't figure it out.

My female gosling looks better this morning. She is walking around. I was talking to a guy who raises them and he said young females are usually lazy and clumsy and take longer to catch up with the males. He said I need to start taking them out a little and let them walk and eat grass. I'm gonna do that. Thanks for the reply Silkiechicken.